Which of the following is correctly matched?

Options

A. Aerenchyma - Opuntia
B. Age pyramid - Biome
C. Parthenium hysterophorus - Threat to biodiversity
D. Stratification - population

Answer

To determine which of the following options is correctly matched, we will analyze each option one by one.

### Step-by-Step Solution:

1. **Option A: Arrankymer and Opentier**
- Arrankymer refers to a type of parenchyma cell with large intercellular spaces filled with air, which helps aquatic plants maintain buoyancy.
- Opentier does not correspond to a recognized biological term related to Arrankymer.
- **Conclusion:** This option is incorrect.

2. **Option B: Age Pyramid and Biome**
- An Age Pyramid represents the distribution of a population across different age groups.
- A Biome is a large ecological area on the earth's surface, with flora and fauna adapting to their environment.
- These two concepts are different and do not directly correlate.
- **Conclusion:** This option is incorrect.

3. **Option C: Parthenium hysterophorus and Threat to Biodiversity**
- Parthenium hysterophorus is indeed a weed native to America that poses a threat to biodiversity by damaging crops (like wheat) and causing health issues in humans (dermatitis and respiratory disorders).
- **Conclusion:** This option is correct.

4. **Option D: Stratification and Population**
- Stratification refers to the arrangement of flora and fauna in vertical layers.
- Population refers to the number of individuals living in a specific area.
- These two concepts are unrelated.
- **Conclusion:** This option is incorrect.

### Final Answer:
The correctly matched option is **Option C: Parthenium hysterophorus and Threat to Biodiversity**.

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